Conventional electric vehicles, including an electric car and a hybrid car, are designed to supply electric power stored in an electric storage device, such as a secondary battery, to an electric motor via an inverter or the like to thereby output a driving force for traveling. Those electric devices including the secondary battery, inverter, electric motor, and the like might malfunction or be broken when reaching high temperature due to self-heating or the like. For this reason, the electric vehicles need to be equipped with a temperature adjustment device for cooling such an electric device.
For example, Patent Document 1 discloses the use of a vapor compression refrigeration cycle device for cooling air to be blown into a vehicle interior in a vehicle air conditioner, as an example of the temperature adjustment device for cooling the electric device. More specifically, the refrigeration cycle device disclosed in Patent Document 1 includes two evaporators connected in parallel. One of the evaporators is adapted to cool the air to be blown into the vehicle interior, while the other one is adapted to cool a heat medium for cooling the electric device.
In other words, the refrigeration cycle device in Patent Document 1 is configured to adjust the temperatures of two types of subjects of temperature adjustment, namely, the air (first temperature-adjustment subject) and the heat medium (second temperature-adjustment subject).